Weekly GSC decay curve

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered; 'Read-only GSC query' largely restates them. The description does add real value by explaining this feeds the verdict engine's decay rules, but it says nothing about rate limits, latency, or data freshness.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two tight sentences, front-loaded with the operation, followed by context and the read-only note. No filler and nothing buried.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need not be explained, and the description still conveys the key output shape (the three trend classes). Combined with annotations covering safety, the definition is nearly complete; only alternative-tool routing guidance is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 50% – url is documented, but weeks has no schema description. The description partially compensates by giving the default ('default 12'), though it omits the schema's 4-52 bounds. Baseline 3 is appropriate given only half the parameters are documented structurally.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource: bucketing GSC clicks/impressions/avg-position into weekly windows and classifying the trend as decay/plateau/growth. The metric set and output classification make the purpose unambiguous. It does not explicitly contrast itself with the sibling posts_verdict, but the resource is distinct enough to disambiguate.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description places the tool in context ('underpins the verdict engine's decay rules'), which implies when it matters, but gives no explicit when-to-use versus alternatives such as posts_verdict or posts_snapshot. Usage is inferable rather than stated, which is the definition of a 3.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.